StackOverflow2013

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copied!<p>I frequently implement my Java swing GUIs using Martin Fowler's <a href="http://martinfowler.com/eaaDev/PresentationModel.html" rel="nofollow">Presentation Model</a> pattern.</p> <p>Here is an example:</p> <pre><code>import java.awt.BorderLayout; import java.awt.event.ActionListener; import javax.swing.BorderFactory; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JList; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.ListModel; interface MainView { void configurationButtonAddActionListener(ActionListener actionListener); void directoryLabelSetText(String text); ListModel fileListGetModel(); void setVisible(final boolean visible); } class MainFrame extends JFrame implements MainView { private final JButton configurationButton = new JButton("Configuration..."); private final JLabel directoryLabel = new JLabel(); private final JList fileList = new JList(); public MainFrame(final String title) { super(title); final JPanel mainPanel = new JPanel(new BorderLayout()); add(mainPanel); mainPanel.setBorder(BorderFactory.createEmptyBorder(12, 12, 12, 12)); mainPanel.add(directoryLabel, BorderLayout.NORTH); mainPanel.add(new JScrollPane(fileList)); mainPanel.add(configurationButton, BorderLayout.SOUTH); setSize(800, 600); setLocationRelativeTo(null); } @Override public void configurationButtonAddActionListener(final ActionListener actionListener) { configurationButton.addActionListener(actionListener); } @Override public void directoryLabelSetText(final String text) { directoryLabel.setText(text); } @Override public ListModel fileListGetModel() { return fileList.getModel(); } } </code></pre> <p>The interface can then be passed to a presenter class that is responsible for handling all actions on the view. A mock version can be passed into the presenter for testing and the view is so simple that, in theory, it does not need to be unit tested.</p> <p>I am trying to do something similar in Clojure using <code>defrecord</code>:</p> <pre><code>(ns mainframe (:gen-class) (:import [java.awt BorderLayout] [javax.swing JButton JFrame JLabel JList JPanel JScrollPane])) (if *compile-files* (set! *warn-on-reflection* true)) (defprotocol MainView (directory-label-set-text [this text]) (set-visible [this visible])) (defrecord mainframe [^JFrame frame directory-label file-list configuration-button] MainView (directory-label-set-text [this text] (.setText directory-label text)) (set-visible [this visible] (.setVisible frame visible))) (defn create-main-frame [title] (let [directory-label (JLabel.) file-list (JList.) configuration-button (JButton. "Configuration...") main-panel (doto (JPanel. (BorderLayout.)) (.add directory-label BorderLayout/NORTH) (.add (JScrollPane. file-list)) (.add configuration-button BorderLayout/SOUTH)) frame (doto (JFrame.) (.setTitle title) (.setDefaultCloseOperation JFrame/EXIT_ON_CLOSE) (.add main-panel) (.setSize 800 600) (.setLocationRelativeTo nil))] (mainframe. frame directory-label file-list configuration-button))) </code></pre> <p>The only way I can up with to do the interface and "class" are using <code>defprotocol</code> and <code>defrecord</code>. Is there a better way? Is there any way to make the "fields" in the <code>defrecord</code> that contain the components (JButton, JLabel, JList) private? I dislike exposing the implementation details.</p>

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